cineselectric salon wrote:
Any amp techs in the house?

I'm possibly getting a Contessa 55-R P.A. head.   It's 50 watts, tube.
Here it is:
http://bartell.vintageusaguitars.com/in … sa_pa_55r/

Does anyone have any ideas for speakers for this?  Most modern PA speakers are rated much higher wattage - around 250 watts.  People have been telling me using the lower powered (50 watt) head will result in blown speakers.

I'm thinking of getting some guitar speaker cabinets to use with it.  I just don't know what to do.

Using a speakers that can handle more power than the amp can deliver will not hurt the speakers.

Using speakers not rated at the correct ohms can (will) cause problems with the amp. IIRC that amp requires 8ohm speakers but I could be wrong - it's been a long time. It should say on the rear panel where the speakers plug in.

SayCheeZ!  wrote:
As with any amplifier, using a lower power amp that's continually peaking will blow a speaker, but if you're peaking often you'll probably hear the result as distortion before it blows anyway.

Any speaker can handle practically any wattage, it's just the duration that's the factor.

News to me.

Lohkee wrote:

News to me.

All he really said there is "all speakers can be blown, just a matter of how long it takes".

Like the time I hit one note with an Ampeg SVT head dimed (my friend turned it all the way up, unknown to me) through a 2-12" open-back cabinet with cheap speakers. The cones shot forward mightily, once. Then there was a puff of yellow smoke. Not even a frequency, you need a full oscillation to determine frequency.

cineselectric salon wrote:

I would be mostly using it for jamming & rehearsals. Running a vocal mic or two, occasionally mic-ing an acoustic guitar.  And maybe mic-ing an acoustic piano.

How loud do you usually play?

Shadow Dancer wrote:
All he really said there is "all speakers can be blown, just a matter of how long it takes".

I took what he said "Any speaker can handle practically any wattage, it's just the duration that's the factor" at face value. Perhaps I read it wrong. I, for one, would not want to hook a 5W speaker up to a 200W amp. It's possible that it may survive 200W for a short amount of time, but I sure wouldn't put any money on it.

I also disagree with his comments on clipping. That is, after all, exactly what a "fuzz box" is designed to do - turn a sine wave into a square wave by using a high-gain pre-amp and two diodes to to clip the input signal. One could also achieve the same affect by simply over-driving the input stage of the amp.

cineselectric salon wrote:

Not too loud, mostly folksy country americana-ish stuff.
And maybe 60ish garage rock... which might get louder, but might sound better with relatively underpowerd gear?

I guess you will find out soon enough!

The tweeters on most modern PA speakers are usually pretty well protected.

Try turning the amp to the desired volume with the treble control turned down, then dial in a reasonable amount of treble and see how it sounds. Probably a safer approach most of the time in any case.

cineselectric salon wrote:

That's what the guys at the guitar stores were telling me when I was asking about their PA speakers they had for sale.  But none of them had any suggestions about what speakers were available that I could use.  Maybe I'll have to look for vintage speakers?

You really need to talk to a technician, or just look at the back of the amp. It should tell you the correct speaker impedance.

Lohkee wrote:

I took what he said "Any speaker can handle practically any wattage, it's just the duration that's the factor" at face value. Perhaps I read it wrong. I, for one, would not want to hook a 5W speaker up to a 200W amp. It's possible that it may survive 200W for a short amount of time, but I sure wouldn't put any money on it.

I also disagree with his comments on clipping. That is, after all, exactly what a "fuzz box" is designed to do - turn a sine wave into a square wave by using a high-gain pre-amp and two diodes to to clip the input signal. One could also achieve the same affect by simply over-driving the input stage of the amp.

I took what he said at face value as well, just translated it into English.

Yes, a 5 watt speaker can handle 200 watts easily for the duration required to destroy the voice coil with heat and/or pummel the spider out of alignment.

My guess would be a duration measured in fractions of a second.

A guitar or voice with a fuzz box will blow a tweeter if it is loud enough which is all anybody has been saying in the first place. When current exceeds heat dissipation, physical components will experience catastrophic failure.

cineselectric salon wrote:
Thanks for all the replies..

Does anyone know what kind of P.A. speakers were used by the common man "back in the day" (mid to late 60's, early 70's)?

Celestions were very common. Also all kinds of generic OEM stuff.

cineselectric salon wrote:
Thanks for all the replies..

Does anyone know what kind of P.A. speakers were used by the common man "back in the day" (mid to late 60's, early 70's)?

Yes, two types predominated.

Altec Voice of the Theater. These were a horn loaded 15" speaker with a GIANT cabinet and a large tweeter horn mounted on top. Huge, heavy and sounded like a vacuum cleaner in a tunnel because the crossover was set too low.

PA columns - typically a vertical array of 4 8" or 10" speakers in a box. No tweeters. Sounded pretty OK at low volumes if you had the treble up and vocals only.

A modern system with a single 10" and tweeter will blow both of those systems off the face of the earth. Even the single 8" speakers are pretty amazing if you get the good stuff. Small, fairly light, full range fidelity and much louder than you would ever expect. Not cheap for good ones, I have used the top line EV and Yamaha 8" two ways and they are jaw dropping for their size. Both had built-in amplifiers, all that was needed was a mixing board.

cineselectric salon wrote:
Thanks for all the replies..

Does anyone know what kind of P.A. speakers were used by the common man "back in the day" (mid to late 60's, early 70's)?

Won't really matter - speakers of that era didn't sound anywhere near as good as current product and they have a limited lifespan anyway. Just pick something with 8 ohm impedance that sounds right to you..

Speakers commonly dropped from 8 ohms to 4 so that power ratings could be increased without boosting amplifier voltage.
Volts x Amps = Watts

Solid state equivalent of the output section (modular) (less preamp, less power supply)  I know it won'r sound the same as a tube amp.
http://www.ebay.com/itm/TDA7492-D-Class … 1267388674

cineselectric salon wrote:

I've seen those before.  Were they British?

No. Most mfgs of speaker enclosures to not actually design and build their own speakers. They just use off-the-shelf parts from other people and assemble them the way they think best.

cineselectric salon wrote:
I've seen those before.  Were they British?

In Europe you would have used Celestion, Rola and many other drivers.

In the USA, primarily Altec Lansing, JBL, Electro-Voice, Jensen, Eminence, Utah and CTS made speakers for PA/guitar/bass/keyboards.

None of them were worth a crap compared to what is available now.

Edit per Lohkee's post. I am referring to the drivers (raw frame speakers). The cabinets were made by Fender, Gibson, Altec and many, many others.

Plus, there was Traynor gear. I don't recall the speaker brand but it was Canadian made and equivalent to the US/European stuff.

cineselectric salon wrote:
I would be mostly using it for jamming & rehearsals. Running a vocal mic or two, occasionally mic-ing an acoustic guitar.  And maybe mic-ing an acoustic piano.

For use as a guitar amp that amp has definite potential. Still, very possible that it may have issues as described above. If you are able to try it out and all seems fine, and the price is good, then it may be worth a gamble if you have discretionary funds.  But even if it seems OK now, it could easily develop issues that could cost much more than the price of the amp itself to repair.

For PA type use, i.e. micing vocals, acoustics, pianos, guitar cabinets, etc I would strongly advise low-impedance (XLR type) microphones and a PA with XLR inputs.

If you were in the US, I would recommend Shure SM57 and/or SM58 mics (good performers, extremely rugged, inexpensive, industry standard) and a 200-500 watt small PA head (pre-amp, amp combined) by Peavey or Mackie. On the scale were are talking, the most common pro-type speakers would typically have a horn tweeter and (usually) a 15" woofer. Peavey, Yamaha, Community would be good brands for inexpensive, fairly well performing, and very durable speakers. You need "full-range" (i.e. has some type of tweeter) to do  justice to a piano, vocals, etc.

Durability IS a significant factor since (hopefully) the gear will get moved back and forth to gigs which means also getting loaded into and out of some type of vehicle twice for each adventure. Sometimes friends (non-owners of said gear) and/or alcohol might be involved. Pro type PA gear, even at the bottom levels, is ruggedly built.

I would have no idea what brands of gear you would have floating around  the used market in Italy. But I would be surprised if the basic designs of such gear was much different there.

As far as "ohms" (aka impedance) go it is not too difficult. Every amp and speaker should have a value printed on it. It will either say "ohms" (or possibly the Italian translation) or it will have the omega symbol (looks like a horse shoe). By far the most common values seen are 4 ohms and 8 ohms. For the speakers this value simply states the impedance (in ohms) of that speaker. For an amp that value indicates the minimum acceptable speaker load impedance in ohms.

It is the amp, not the speakers, that would be vulnerable in the case of a mismatch. For solid state amps (NOT tube), the lower the value of the speaker load the harder the amp is forced to work. When you add a second speaker to a channel of an amp, the speaker load impedance goes down. For example, if you have 8-ohm speakers and you connect two of them to a single amp channel, the speaker load impedance seen by that amp channel would be 4 ohms.

Speakers are most often rated at 8-ohms. Amps are most often able to handle down to 4-ohms load. But there are exceptions. Also, I am talking about gear common in the US, don't know about Europe. So be sure to check whatever you end up buying or using.

cineselectric salon wrote:

oops, my apologies are in order... I don't actually live in Italy, I set my location for there in advance of an upcoming trip there.  I forgot I had done that.  I'm in the U.S.

In that case...Shure/Peavey/Yamaha/Mackie might just be your friends. Traynor was mentioned in this thread and I have good feelings about them too. I believe they have been referred to as the Canadian Peavey...or something like that.

BTW, Peavy is a brand that may be snickered at by those at the upper levels of the sound reproduction world. But it is a brand that has, for decades, produced better than decent quality, very rugged and affordable gear. While it also competes at the upper levels, it is more well known as working class gear. The used market in the US will likely have more Peavey stuff available than any other brand. It is almost like an alternate form of currency, lol.

roger alan wrote:

In that case...Shure/Peavey/Yamaha/Mackie might just be your friends. Traynor was mentioned in this thread and I have good feelings about them too. I believe they have been referred to as the Canadian Peavey...or something like that.

BTW, Peavy is a brand that may be snickered at by those at the upper levels of the sound reproduction world. But it is a brand that has, for decades, produced better than decent quality, very rugged and affordable gear. While it also competes at the upper levels, it is more well known as working class gear. The used market in the US will likely have more Peavey stuff available than any other brand. It is almost like an alternate form of currency, lol.

I've worked on a few Peaveys. I always thought they had a very nice build quality.

roger alan wrote:

In that case...Shure/Peavey/Yamaha/Mackie might just be your friends. Traynor was mentioned in this thread and I have good feelings about them too. I believe they have been referred to as the Canadian Peavey...or something like that.

BTW, Peavy is a brand that may be snickered at by those at the upper levels of the sound reproduction world. But it is a brand that has, for decades, produced better than decent quality, very rugged and affordable gear. While it also competes at the upper levels, it is more well known as working class gear. The used market in the US will likely have more Peavey stuff available than any other brand. It is almost like an alternate form of currency, lol.

Plus a million on the Peavey statements. The resale value of Peavey gear is far lower than it should be, creating a bargain opportunity. Keep your eyes open, craigslist, pawn shops, music stores, antique stores - I've bought Peavey gear in all those places and also at yard sales.

My current PA is a Mackie all in one with 6 channels and a pair of Peavey 12" 2-way speakers. Craigslist - Dad bought it for his kids and they all moved away. $150 for all three pieces. Work horse, always sounds good, takes a beating, if it dies I'll just toss it and get more.

cineselectric salon wrote:

This is what I really want. 


Kustom Series 300. Supposedly, Johnny Cash used it:
http://www.kustom.com/MessageCenterDeta … entID=1403

I've used gear like that, it's not really all that great. Looks totally cool though!!!!

You will never get that crisp, defined sound that makes you feel like it's easy to sing.